LDA X
BSA SH4
STA X
LDA Y
BSA SH4
STA Y
HLT
X, HEX 2
Y, HEX 4321

SH4, HEX 0
CIL
CIL
CIL
CIL
AND MSK
BUN SH4 I
MSK, HEX FFF0
END
